rr: add FSR Ray Regeneration, exact RDNA3 inference and motion experiments

Add an experimental FSR Ray Regeneration backend for D3D12 RR requests:
- Convert depth, motion, normals and albedos into AMD denoiser inputs.
- Split and recompose diffuse/specular signals, then run Super Sampling.
- Add stability/detail controls, demodulation guards and halo limiting.
- Handle AMD provider discovery under NVIDIA GPU spoofing.
- Add runtime probes, synthetic reference scenes and per-dispatch profiling.

Add exact gfx11 DLSS-RR inference using f16 cooperative matrices:
- Reproduce FP8 conversions, accumulation and camera reprojection arithmetic.
- Widen model weights and avoid requiring VK_EXT_shader_float8.
- Extend model building, replay tools and descriptor metadata.

Expand motion preprocessing and experimental AW2 native-motion support:
- Add tiled LDS dilation, padded allocation handling and thin-only sky fill.
- Order dilation with input waits and NGX on the selected stream.
- Add jitter-aligned native composition, hybrid routing and wire history repair.
- Add prepared masks, sparse repair and independent motion/repair controls.

Add optional fused R11G11B10 input/output conversion, sampled stage timings
and profile summarization. Extend configuration, packaging, documentation,
FidelityFX headers and CPU/GPU regression coverage.

scripts/build_rr_backend_check.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Builds build/rr_backend_check.exe (tools/rr_backend_check.cpp): a DLSS Ray Reconstruction request
+# through d4r_nvngx.dll, measured against the synthetic scene's ground truth. Builds the shim first,
+# for the NGX parameter object it links against.
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+MINGW_CXX="${MINGW_CXX:-x86_64-w64-mingw32-g++}"
+
+"$ROOT/scripts/build_d4r_nvngx_shim.sh" >/dev/null
+"$MINGW_CXX" -std=c++20 -O2 -Wall -Wextra -Wno-missing-field-initializers -static -static-libgcc -static-libstdc++ \
+  "$ROOT/tools/rr_backend_check.cpp" "$ROOT/tools/d4r_ngx_param_host.cpp" "$ROOT/build/d4r_ngx_param_msvc.obj" \
+  -ld3d12 -ldxgi -o "$ROOT/build/rr_backend_check.exe"
+printf 'Built %s\n' "$ROOT/build/rr_backend_check.exe"